title: Synthesis and photo-degradation application of WO3/TiO2 hollow spheres.
abstract: A WO(3)/TiO(2) composite, hollow-sphere photocatalyst with average diameter of 320 nm and shell thickness of 50 nm was successfully prepared using a template method. UV-vis diffuse reflectance spectra illustrated that the main absorption edges of the WO(3)/TiO(2) hollow spheres were red-shifted compared to the TiO(2) hollow spheres, indicating an extension of light absorption into the visible region of the composite photocatalyst. The WO(3) and TiO(2) phases were confirmed by X-ray diffraction analysis. BET isotherms revealed that the specific surface area and average pore diameter of the hollow spheres were 40.95 m(2)/g and 19 nm, respectively. Photocatalytic experiments indicate that 78% MB was degraded by WO(3)/TiO(2) hollow spheres under visible light within 80 min. Under the same conditions, only 24% MB can be photodegraded by TiO(2). The photocatalytic mineralization of MB, catalyzed by TiO(2) and WO(3)/TiO(2), proceeded at a significantly higher rate under UV irradiation than that under visible light, and more significant was the increase in the apparent rate constant with the WO(3)/TiO(2) composite semiconductor material which was 3.2- and 3.5-fold higher than with the TiO(2) material under both UV and visible light irradiation. The increased photocatalytic activity of the coupled nanocomposites was attributed to photoelectron/hole separation efficiency and the extension of the wavelength range of photoexcitation.
authors.affiliation: Key Laboratory of Resource Chemistry of Nonferrous Metals, Ministry of Education, China, College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
authors.forename: Kezhen
authors.initials: K
authors.lastname: Lv
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Qing
authors.forename: Wenzhang
authors.initials: W
authors.lastname: Li
authors.forename: Qiyuan
authors.initials: Q
authors.lastname: Chen
mesh_terms: D008027:Light; D053761:Nanocomposites / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D010782:Photolysis; D016062:Porosity; D014025:Titanium / Q000737:chemistry*; D014414:Tungsten / Q000737:chemistry*; D014466:Ultraviolet Rays
chemical_list: D010087:Oxides; C009495:titanium dioxide; C511604:tungsten oxide; D014025:Titanium; D014414:Tungsten